Packing



Feb. 5, 11923.

G. B. GATES PACKING Original Filed Apr I n'uentor:

Witne sses'.

13% WiW 7%. MAM/(Q.

Patented Feb. fi, i923.

WE la PACKING.

Application filed April 30, 1913, Serial No. 764,589.

T 0 all whom it may concern:

Be it known that GEORGE E. GATES, a citizen of the United States,residing at Boston, in the county of Suffolk and State of Massachusetts,has invented certain new and useful Improvements in Packings, of whichthe following is a specification.

My inventionrelates to a stui'ling box for plastic packing, such as isused for packing piston and valve rods, pump plungers and similarmechanism.

One of the difiiculties of making an edicient packing of the plastictype when used in the ordinary way in a stufiing box having parallelsides, is that when pressure is exerted by the follower against therings to force them into contact with the rod that the rings arecompressed in the wrong direction (parallel with the rods). This tendsto harden the packing material by direct pressure against the end of thestuffing box and results in a considerable damage to its plasticproperties. This action is still turther emphasized it the packing i.atei'ial be of a metallic natu which is the most eiii cient in respectof durability and freedom from friction.

Usually the plastic packing material, when metallic, is composed ofparticles of a suitable alloy or composition to possess the desirablecharacteristics and may or may not be mixed with graphite, greases, orsimilar lubricants.

When in use, the metal particles under pressure of the follower, areforced into contact with the rod and the attrition of the rod soon rubsthe particles immediately surrounding it into a practically continuousmetallic skin which acts as a close fitting sleeve in which the rod runsfluid tight. When from wear it requires adjustment the application ormore follower pressure forces the packing against the rod and permits arenewal of the fit.

A few repetitions of this process with the addition of new rings at theouter end to compensate for wear and compressions have heretoforeresulted in the metal particles at the inner end becoming hardened andmore or less amalgamated together and largel losing their ability toflow and to move one upon the other upon which the pl is characteristicsof the mass largely depend. The

fact that the greatest wear and the consequent necessity for renewal oithe lit occurs at the inner or cylinder end, and that Renewed November9, 3.5..0. Serial No. 22,967.

usually the destruction of the rings is involved in their to replace thedetective heretofore made packing expensive tor general use.

The object of the intention is: first, to construct a recs} "acle thatwill have a progressive wedging action upon a substantial portion oi thepacking material the inner end to force it against the red when pressureis applied by the follower; and second, to produce improved structure ofstuiiing hop; in which a plastic packing material may be passed throughthe stutling box and entirely utilized or eliminated when it becomesuseless by disintegration.

It carry out the above objects by means of the instrumentalitieshereinafter described and claimed.

lily iove tion may best be understood by means the accompanying drawing,in which shown a stui'ling hon constructed in aecordaice with myinvention and with a strand of metallic packing adapted to be .ed in thesame.

the drawing,

l. is a longitudinal section through tuiiing box,

2 is a section on the line of 1,

newer outer removal in order inner rings, has of this type too Fig. 3 isa view of a portion of a strand soft metal packing.

in the drawing, a represents the rod to be packed which may be rotatingor reciprocating longitudinally c is the follower which is forced inwardby screws (not shown) in the usual way.

The inner surface of the cup section is so formed as to produce aninwardly tapering annular recess which tends to force the packingagainst the rod as the former is forced inward by the follower. As hereshown, the stuiling box is bored out parallel 1nd the tapering recess isformed by a cup-shaped bushi f which is slipped into the stutling box.The initial bevel of the bushing slopes inwardly and toward the rodcommencing at a point somedistance in from the end of the stul ing boxand at its inner end it is rounded on so that the end of the recessmakes a more obtuse angle with the surface of the rod than the generalsurrace of the outer wall of the recess. The bushing 7 is composedpreferably of non-compressible composition metal.

here shown, 1 form the packing into rings (Z and e and these rings asthey are follower they assume the conical form shown at e in Fig. 1. p

The packing which I prefer to use is plas' tic metallic packing made upof filaments of soft metal formed into a strand and impreg' natedwith'lubricant as grease and graphite. In carrying out this part of myinvention I together metal particles of different alloys or compositionsof different degrees of hardness, which resist the tendency tomassainalgamation without materially affecting the property ofattritio-n-amalgamation.

In practice I largely make use of alloys of lead, tin and antimony andobtain the different degrees of hardness by varying the proportions ofthese metals. In Fig. 8 is. shown a strand or portion of a ring made upof metal filaments laid in substantially parallel order having suitablelubricants intermingled throughout. A plastic metallic packing when madeup as above described, namely, as a mass of filaments or particles, saidfilaments or particles will, under compression, have the quality offlowing or moving more or less freely over each other and as the mass isforced inward into the cup section the cross section of the packing isconstantly changing, breaking up its previous formation and tending tokeep the mass plastic until it is worn out at the apex of the cone. Theresult is practically a perpetual packing, being capable of renewal atthe outer end as it is worn out at the inner end.

I claim 1. An outwardly opening stuffing box having a cylindricalportion parallel with the shaft, a conical portion at the inner end ofsaid cylindrical portion terminating in conical inner end more obtuse tothe shaft than said conical portion, a follower tting in the outer endof cylindricalportion whereby a continuous supply of packing may bepassed through the stuffing box and entirely utilized.

2. Ln outwardly opening stufling box having a cylindrical portionparallel. with the rod or shaft, a conical portion terminating in aportion having amore obtuse bevel to the rod or, shaft, a plasticpacking mate rial in the box and a follower adapted to force the packingmaterial inward.

3. An outwardly opening stuffing boX having a cylindrical portionparallel with he rod or shaft, a conical portion terminat- .ing in aportion ht ving a more obtuse bevel to the rod or shaft and a followeradapted to force packing material toward the obtuse bevel.

In testimony whereof I have affixed my signature, in presence of twowitnesses.

GEORGE E. earns.

Witnesses:

S. W. Barns. C. B. CnnreHToN.

